Magnesium and manganese may be confused with each other because of their similar names and chemical symbols. But, there are many notable differences between these elements in several properties, be they general, atomic, thermodynamic, or electromagnetic.

Magnesium is a group-2 metal, an s-block element with the symbol Mg and atomic number 12. It is a shiny gray solid resembling the other alkaline earth metals. On the other hand, Manganese is a transition metal, a d-block element, with the symbol Mn and atomic number 25. It is never found as a free element but rather in minerals.

Both magnesium and manganese are metals and possess common properties like all metals. Another similarity is that magnesium, as well as manganese, are paramagnetic in nature. Also, both elements are conductors of electricity.

However, there are some main differences in properties between the two elements.

Magnesium vs Manganese

Magnesium (Mg) Manganese (Mn)
Magnesium is in s block of the periodic table Manganese is a d block element
The symbol of magnesium is mg The symbol of manganese is Mn
The electronic configuration of magnesium is [Ne]3s2
The electron configuration of manganese is given as [Ar]3d54s2
Its electronegativity value is 1.31 Its electronegativity value is 1.55
Being a macro-mineral, it is needed in a larger amounts (350mg/day) for human bodies Manganese is a micromineral and is required in trace amounts (2.3mg/day) 
It is a representative element It is a transition metal
Magnesium oxide (MgO), also known as magnesia, is the most common compound of magnesium One of most common compound of manganese is KMnO4, potassium permanganate
Magnesium has a wide range of applications as a metal, especially in aircraft designing and automotive designing  Manganese is used in the production of steel. Manganese acts as a deoxidizing and alloying agent 

1. General properties

Magnesium is present in group 2A and the 3rd period in the periodic table. Manganese exists in the 7th group and the 4th period in the first transition series.

The crystal structure of magnesium is hexagonal and close-packed whereas that of manganese is body-centered cubic.

The relative atomic mass of magnesium is 24.3050 a.m.u while that of Manganese is 54.9380 a.m.u.

Magnesium has a density of 1.738 g/cm3 and manganese has 7.21 g/cm3.

The melting and boiling points of magnesium are 650 °C and 1090 °C. The melting and boiling points of manganese are 1242°C and 2061°C.

Magnesium has an electronegativity of 1.31 and manganese has a value of 1.55 on Pauling’s scale.

2. Atomic properties

Magnesium, 12Mg has an electronic configuration of 1s2 2s2 2p6 3s2 whereas manganese, 25Mn has an electronic configuration of 1s2 2s2 2p6 3s2 3p6 3d5 4s2.

Magnesium has 2 valence electrons in the 3s orbital and forms a +2 ion. On the other hand, manganese, being a transition metal, has multiple oxidation states ranging from -3 to +7, although the most common are +2, +3, +4, +5, +6, and +7.

The ionization potential for an atom of magnesium is 7.61 eV and for manganese, it is 7.40 eV.

Magnesium has an atomic radius of 160 pm while manganese has 127 pm.

3. Thermodynamic properties

The heat of fusion of magnesium is 8.7 kJmol-1 and that of manganese is 13.2 kJmol-1.

The heat of vaporization for magnesium is 128 kJmol-1 and for manganese, it’s 220 kJmol-1.

Magnesium has a specific heat of 1.02 J/g.K while manganese has 0.479 J/g.K.

The thermal expansion of magnesium is 24.8 x 10-6 /°C and that of manganese is 21.7 x 10-6 /°C.

4. Electromagnetic properties

The electrical conductivity of magnesium is 2.3 x 107 S/m and that of manganese is 6.2 x 105 S/m.

The resistivity of magnesium is 4.4 x 10-8 Ωm and of manganese, it’s 1.6 x 10-7 Ωm.

The molar magnetic susceptibility of magnesium is 1.68 x 10-10 m3mol-1 and that of manganese is 6.6475 x 10-9 m3mol-1.

5. Biological aspects

Magnesium and manganese are two of the essential minerals that are required for the human body to function. Manganese is a micromineral required in trace amounts (2.3 mg/day). Comparatively, magnesium, being a macromineral, is needed in larger amounts (350 mg/day).

Manganese functions as an enzyme cofactor and helps in metabolism, bone formation, and blood clotting. Magnesium, on the contrary, is required for blood pressure regulation, energy production, and nerve and muscle function, in addition to being an enzyme cofactor.

Both minerals help with bone health and lower the risk of diabetes, etc.

Manganese is found in brown rice, chickpeas, oysters, hazelnuts, pecans, etc. Magnesium can be found in pumpkin and chia seeds, almonds, peanuts, cashews, spinach, etc.

Related topics

Key differences between Mg and Mn

Difference between Magnesium vs Manganese

Concepts Berg

Does magnesium reduce inflammation?

Magnesium deficiency is linked to inflammation due to increased oxidative stress. By the research-based information provided, magnesium is bound to reduce inflammation caused by oxidative stress.

Why is manganese bad?

Manganese is required in trace amounts of 2.3 mg per day. Like everything else, an excess of manganese is bad for health. It might have adverse effects on brain function, memory, mood, etc.

Who should not take manganese?

Manganese is unsafe when inhaled by children. It can come from welding fumes and contaminated water. Magnesium exposure is linked to intellectual impairment in children.

What are the symptoms of low manganese?

The symptoms of low manganese include poor bone growth, low fertility, impaired glucose tolerance, and abnormal metabolism of fats and carbohydrates.

Are manganese and magnesium the same?

Although the two elements have similar-sounding names and chemical symbols, the two are vastly different in their properties. Manganese has the properties shared by other transition metals while magnesium, being an alkaline earth metal, shows its properties as such.

Is it OK to take magnesium every day?

Magnesium, being a macromineral, has a recommended dietary allowance of about 350 mg per day. Any more amount than this would result in hypermagnesemia causing cardiovascular and nervous issues.

How do you know if you’re getting too much magnesium?

The symptoms of having too much magnesium include low blood pressure, nausea, diarrhea, muscle weakness, fatigue, etc.

What are the benefits of manganese?

Manganese is an anti-oxidant and halts cellular oxidation. It also helps in brain and bone development, regulates blood pressure, and may help against diabetes.

Manganese vs magnesium in water.

Manganese does not react with water under normal conditions. On the contrary, magnesium has a slight reaction with cold water, forming hydrogen gas bubbles. With hot water, magnesium reacts faster and produces magnesium hydroxide along with hydrogen gas.

Which metal is more reactive, magnesium or zinc?

From the activity series of metals (electrochemical series), we can see that magnesium is more reactive than zinc.

How do non-ferromagnesian minerals differ from ferromagnesian minerals?

Ferromagnesian minerals contain iron and magnesium cations whereas non-ferromagnesian minerals do not. Non-ferromagnesian minerals are generally light-colored.

How does magnesium react with nitric acid?

When magnesium reacts with dilute nitric acid, hydrogen gas is evolved and magnesium nitrate is formed.

Mg + 2HNO3 → Mg(NO3)2 + H2